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Pull perf tools fixes from Namhyung Kim:
"Just a couple of build fixes on arm64"
* tag 'perf-tools-fixes-for-v6.15-2025-05-04' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools:
perf tools: Fix in-source libperf build
perf tools: Fix arm64 build by generating unistd_64.h
Pull tracing fixes from Steven Rostedt:
- Fix read out of bounds bug in tracing_splice_read_pipe()
The size of the sub page being read can now be greater than a page.
But the buffer used in tracing_splice_read_pipe() only allocates a
page size. The data copied to the buffer is the amount in sub buffer
which can overflow the buffer.
Use min((size_t)trace_seq_used(&iter->seq), PAGE_SIZE) to limit the
amount copied to the buffer to a max of PAGE_SIZE.
- Fix the test for NULL from "!filter_hash" to "!*filter_hash"
The add_next_hash() function checked for NULL at the wrong pointer
level.
- Do not use the array in trace_adjust_address() if there are no
elements
The trace_adjust_address() finds the offset of a module that was
stored in the persistent buffer when reading the previous boot buffer
to see if the address belongs to a module that was loaded in the
previous boot. An array is created that matches currently loaded
modules with previously loaded modules. The trace_adjust_address()
uses that array to find the new offset of the address that's in the
previous buffer. But if no module was loaded, it ends up reading the
last element in an array that was never allocated.
Check if nr_entries is zero and exit out early if it is.
- Remove nested lock of trace_event_sem in print_event_fields()
The print_event_fields() function iterates over the ftrace_events
list and requires the trace_event_sem semaphore held for read. But
this function is always called with that semaphore held for read.
Remove the taking of the semaphore and replace it with
lockdep_assert_held_read(&trace_event_sem)
* tag 'trace-v6.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Do not take trace_event_sem in print_event_fields()
tracing: Fix trace_adjust_address() when there is no modules in scratch area
ftrace: Fix NULL memory allocation check
tracing: Fix oob write in trace_seq_to_buffer()
When libperf is built alone in-source, $(OUTPUT) isn't set. This causes
the generated uapi path to resolve to '/../arch' which results in a
permissions error:
mkdir: cannot create directory '/../arch': Permission denied
Fix it by removing the preceding '/..' which means that it gets
generated either in the tools/lib/perf part of the tree or the OUTPUT
folder. Some other rules that rely on OUTPUT further refine this
conditionally depending on whether it's an in-source or out-of-source
build, but I don't think we need the extra complexity here. And this
rule is slightly different to others because the header is needed by
both libperf and Perf. This is further complicated by the fact that Perf
always passes O=... to libperf even for in source builds, meaning that
OUTPUT isn't set consistently between projects.
Because we're no longer going one level up to try to generate the file
in the tools/ folder, Perf's include rule needs to descend into libperf.
Also fix the clean rule while we're here.
Reported-by: Thorsten Leemhuis <linux@leemhuis.info>
Closes: https://lore.kernel.org/linux-perf-users/7703f88e-ccb7-4c98-9da4-8aad224e780f@leemhuis.info/
Fixes: bfb713ea53c7 ("perf tools: Fix arm64 build by generating unistd_64.h")
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Thorsten Leemhuis <linux@leemhuis.info>
Link: https://lore.kernel.org/r/20250429-james-perf-fix-libperf-in-source-build-v1-1-a1a827ac15e5@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Merge tag 'parisc-for-6.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fix from Helge Deller:
"Fix a double SIGFPE crash"
* tag 'parisc-for-6.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix double SIGFPE crash
On some paths in print_event_fields() it takes the trace_event_sem for
read, even though it should always be held when the function is called.
Remove the taking of that mutex and add a lockdep_assert_held_read() to
make sure the trace_event_sem is held when print_event_fields() is called.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250501224128.0b1f0571@batman.local.home
Fixes: 80a76994b2d88 ("tracing: Add "fields" option to show raw trace event fields")
Reported-by: syzbot+441582c1592938fccf09@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6813ff5e.050a0220.14dd7d.001b.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since pulling in the kernel changes in commit 22f72088ffe6 ("tools
headers: Update the syscall table with the kernel sources"), arm64 is
no longer using a generic syscall header and generates one from the
syscall table. Therefore we must also generate the syscall header for
arm64 before building Perf.
Add it as a dependency to libperf which uses one syscall number. Perf
uses more, but as libperf is a dependency of Perf it will be generated
for both.
Future platforms that need this will have to add their own syscall-y
targets in libperf manually. Unfortunately the arch specific files that
do this (e.g. arch/arm64/include/asm/Kbuild) can't easily be imported
into the Perf build. But Perf only needs a subset of the generated files
anyway, so redefining them is probably the correct thing to do.
Fixes: 22f72088ffe6 ("tools headers: Update the syscall table with the kernel sources")
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20250417-james-perf-fix-gen-syscall-v1-1-1d268c923901@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Pull EDAC fixes from Borislav Petkov:
- Test the correct structure member when handling correctable errors
and avoid spurious interrupts, in altera_edac
* tag 'edac_urgent_for_v6.15_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/altera: Set DDR and SDMMC interrupt mask before registration
EDAC/altera: Test the correct error reg offset
Camm noticed that on parisc a SIGFPE exception will crash an application with
a second SIGFPE in the signal handler. Dave analyzed it, and it happens
because glibc uses a double-word floating-point store to atomically update
function descriptors. As a result of lazy binding, we hit a floating-point
store in fpe_func almost immediately.
When the T bit is set, an assist exception trap occurs when when the
co-processor encounters *any* floating-point instruction except for a double
store of register %fr0. The latter cancels all pending traps. Let's fix this
by clearing the Trap (T) bit in the FP status register before returning to the
signal handler in userspace.
The issue can be reproduced with this test program:
root@parisc:~# cat fpe.c
static void fpe_func(int sig, siginfo_t *i, void *v) {
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGFPE);
sigprocmask(SIG_UNBLOCK, &set, NULL);
printf("GOT signal %d with si_code %ld\n", sig, i->si_code);
}
int main() {
struct sigaction action = {
.sa_sigaction = fpe_func,
.sa_flags = SA_RESTART|SA_SIGINFO };
sigaction(SIGFPE, &action, 0);
feenableexcept(FE_OVERFLOW);
return printf("%lf\n",1.7976931348623158E308*1.7976931348623158E308);
}
root@parisc:~# gcc fpe.c -lm
root@parisc:~# ./a.out
Floating point exception
root@parisc:~# strace -f ./a.out
execve("./a.out", ["./a.out"], 0xf9ac7034 /* 20 vars */) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0
...
rt_sigaction(SIGFPE, {sa_handler=0x1110a, sa_mask=[], sa_flags=SA_RESTART|SA_SIGINFO}, NULL, 8) = 0
--- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0x1078f} ---
--- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0xf8f21237} ---
+++ killed by SIGFPE +++
Floating point exception
Signed-off-by: Helge Deller <deller@gmx.de>
Suggested-by: John David Anglin <dave.anglin@bell.net>
Reported-by: Camm Maguire <camm@maguirefamily.org>
Cc: stable@vger.kernel.org
The function trace_adjust_address() is used to map addresses of modules
stored in the persistent memory and are also loaded in the current boot to
return the current address for the module.
If there's only one module entry, it will simply use that, otherwise it
performs a bsearch of the entry array to find the modules to offset with.
The issue is if there are no modules in the array. The code does not
account for that and ends up referencing the first element in the array
which does not exist and causes a crash.
If nr_entries is zero, exit out early as if this was a core kernel
address.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250501151909.65910359@gandalf.local.home
Fixes: 35a380ddbc653 ("tracing: Show last module text symbols in the stacktrace")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull x86 fix from Ingo Molnar:
"Fix SEV-SNP memory acceptance from the EFI stub for guests
running at VMPL >0"
* tag 'x86-urgent-2025-05-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot/sev: Support memory acceptance in the EFI stub under SVSM
Mask DDR and SDMMC in probe function to avoid spurious interrupts before
registration. Removed invalid register write to system manager.
Fixes: 1166fde93d5b ("EDAC, altera: Add Arria10 ECC memory init functions")
Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@altera.com>
Signed-off-by: Matthew Gerlach <matthew.gerlach@altera.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Cc: stable@kernel.org
Link: https://lore.kernel.org/20250425142640.33125-3-matthew.gerlach@altera.com
The check for a failed memory location is incorrectly checking
the wrong level of pointer indirection by checking !filter_hash
rather than !*filter_hash. Fix this.
Cc: asami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250422221335.89896-1-colin.i.king@gmail.com
Fixes: 0ae6b8ce200d ("ftrace: Fix accounting of subop hashes")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The C sequence points are complicated things, and gcc-15 has apparently
added a warning for the case where an object is both used and modified
multiple times within the same sequence point.
That's a great warning.
Or rather, it would be a great warning, except gcc-15 seems to not
really be very exact about it, and doesn't notice that the modification
are to two entirely different members of the same object: the array
counter and the array entries.
So that seems kind of silly.
That said, the code that gcc complains about is unnecessarily
complicated, so moving the array counter update into a separate
statement seems like the most straightforward fix for these warnings:
drivers/net/wireless/intel/iwlwifi/mld/d3.c: In function ‘iwl_mld_set_netdetect_info’:
drivers/net/wireless/intel/iwlwifi/mld/d3.c:1102:66: error: operation on ‘netdetect_info->n_matches’ may be undefined [-Werror=sequence-point]
1102 | netdetect_info->matches[netdetect_info->n_matches++] = match;
| ~~~~~~~~~~~~~~~~~~~~~~~~~^~
drivers/net/wireless/intel/iwlwifi/mld/d3.c:1120:58: error: operation on ‘match->n_channels’ may be undefined [-Werror=sequence-point]
1120 | match->channels[match->n_channels++] =
| ~~~~~~~~~~~~~~~~~^~
side note: the code at that second warning is actively buggy, and only
works on little-endian machines that don't do strict alignment checks.
The code casts an array of integers into an array of unsigned long in
order to use our bitmap iterators. That happens to work fine on any
sane architecture, but it's still wrong.
This does *not* fix that more serious problem. This only splits the two
assignments into two statements and fixes the compiler warning. I need
to get rid of the new warnings in order to be able to actually do any
build testing.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull misc perf fixes from Ingo Molnar:
- Require group events for branch counter groups and
PEBS counter snapshotting groups to be x86 events.
- Fix the handling of counter-snapshotting of non-precise
events, where counter values may move backwards a bit,
temporarily, confusing the code.
- Restrict perf/KVM PEBS to guest-owned events.
* tag 'perf-urgent-2025-05-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: KVM: Mask PEBS_ENABLE loaded for guest with vCPU's value.
perf/x86/intel/ds: Fix counter backwards of non-precise events counters-snapshotting
perf/x86/intel: Check the X86 leader for pebs_counter_event_group
perf/x86/intel: Only check the group flag for X86 leader
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